KR101631829B1 - Method of manufacturing phosphor in glass using nano glass powder and white light emitting device - Google Patents

Abstract

Disclosed are a manufacturing method of a color converting material using nano glass powder, and a white light emitting device. The manufacturing method of a color converting material in the present invention is a method for manufacturing phosphor in glass (PIG) which is a color converting material arranged on the front of an LED. The manufacturing method comprises following steps: forming nano glass powder having an average diameter of 100 nm or less by pulverizing a mother glass; forming a mixture by mixing the nano glass powder and a fluorescent; forming a molded object by molding the mixture; and plasticizing the molded object. The manufacturing method can suppress a reaction with a fluorescent by lowering the plasticization temperature using nano glass powder, and can manufacture a color converting material having excellent optical transmittance.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing a color conversion material using nano glass powder,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology for manufacturing phosphor-based glass (PIG) for LEDs, and more particularly to a method of manufacturing a color conversion material having excellent color conversion efficiency and light transmittance using nano- will be.

A phosphor is required for emitting white light from an LED emitting monochromatic light such as blue light.

As the method of implementing the phosphor, the following three main methods are used.

The first is a method of molding silicon mixed with a yellow phosphor on a blue LED chip. In the case of a white LED package manufactured in this form, yellowing occurs due to deterioration of a color conversion material at a high temperature, and further, reliability is deteriorated due to gas and moisture permeation.

Secondly, the yellow phosphor is dispersed and molded in an organic material such as epoxy. In this case, too, there is a problem that the heat resistance is weak due to the use of the organic material.

The third is a method of mounting a phosphor glass (PIG) in which a yellow phosphor is dispersed in glass in a cover form. In this case, the problem of high temperature deterioration as described above can be solved, and resistance to gas and moisture penetration is also excellent. In this case, firing should be performed at a sufficiently high temperature to increase the light transmittance. However, in the case of high-temperature baking, a problem of phosphor deterioration often occurs.

Background art related to the present invention is a rare-earth ion-containing glass-phosphor composite disclosed in Korean Patent Laid-Open Publication No. 10-2014-0106332 (published on Apr. 31, 2013.03) and a light emitting diode including the same.

It is an object of the present invention to provide a method of manufacturing a color conversion material which can lower the firing temperature by using nano glass powder and can suppress the reaction with the phosphor and has an excellent light transmittance.

Another object of the present invention is to provide a white light emitting device having excellent color conversion efficiency and light transmittance even when the temperature is increased to 200 DEG C or higher in driving a light emitting device.

According to an aspect of the present invention, there is provided a method of manufacturing a color conversion material (PIG) for color conversion, the method comprising the steps of: Forming a nano-sized glass powder; Mixing the nano glass powder and the phosphor to form a mixture; Forming a molded body by molding the mixture; And firing the molded body.

According to another aspect of the present invention, there is provided a method of fabricating a color conversion material disposed on a front surface of an LED, the method comprising: forming a nano glass powder having an average particle size of 100 nm or less; ; Preparing a paste including the nano glass powder and the phosphor; And applying the paste to a substrate glass, followed by baking.

At this time, the nano glass powder is composed of 55 to 70% of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% of CaO or less and 2 to 10% of SrO, R ₂ O (R = Li, Na, K, Rb and Cs), Sb ₂ O ₃ , F, Cl, SO ₃ , P ₂ O ₅ , V ₂ O ₅ , PbO, ZnO and Bi ₂ O ₃ It may not be added.

The nano glass powder may contain 55 to 70% of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% or less of CaO, 2 to 10% of SrO, 5 to 10% of MgO % or less, and BaO: is composed of at least one of 5 weight% or _{less, R 2 O (R = Li} , Na, K, Rb and _{Cs), Sb 2 O 3,} F, Cl, SO 3, P 2 O 5 , V ₂ O ₅ , PbO, ZnO and Bi ₂ O ₃ may not be intentionally added.

Also, the phosphor may be (Lu _x Ce _1-x ) ₃ Al ₅ O ₁₂ (0.75 _{? X} ? 0.95).

According to another aspect of the present invention, there is provided a white light emitting device including an LED and a phosphor in glass (PIG) disposed on a front surface of the LED, the LED emitting blue light, The conversion material is characterized in that a yellow phosphor is dispersed in the glass, and the yellow phosphor is (Lu _x Ce _1-x ) ₃ Al ₅ O ₁₂ (0.75 _{? X} ? 0.95).

In this case, the glass is made of, by _{weight%, SiO 2 55 ~ 70%} , Al 2 O 3 10 ~ 22%, B 2 O 3 1 ~ 15%, or less, and SrO 2 ~ 10% CaO 10% , R 2 O (R = Li, Na, K, Rb and _{Cs), Sb 2 O 3,} F, Cl, SO 3, P 2 O 5, V 2 O 5, PbO, ZnO and Bi ₂ O ₃ is not intentionally added It may not be.

Also, the glass preferably contains 55 to 70% of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% or less of CaO, 2 to 10% of SrO, 5% and BaO: is composed of at least one of 5 weight% or _{less, R 2 O (R = Li} , Na, K, Rb and _{Cs), Sb 2 O 3,} F, Cl, SO 3, P 2 O 5, V ₂ O ₅ , PbO, ZnO and Bi ₂ O ₃ may not be intentionally added.

According to the method for producing a color conversion material using the nano glass powder according to the present invention, the firing temperature can be lowered without lowering the light transmittance by using the characteristic that the firing temperature is lowered as the size of the glass powder is nanoized. It is possible to prevent deterioration in color conversion efficiency.

(Lu _x Ce _1-x ) ₃ Al ₅ O ₁₂ (0.75 _{? X} ? 0.95), which is mainly used as a green phosphor, was fired together with glass powder to prepare a color conversion material and applied to a white light emitting device. As a result, And even when the temperature is increased to 200 DEG C or more during LED operation, the decrease of the phosphor characteristics is not so large, and the effect of deterioration of the light output characteristic is not so large even at a high temperature.

FIG. 1 shows a characteristic change of (Lu _0.9 Ce _0.1 ) ₃ Al ₅ O ₁₂ phosphor with temperature.
2 schematically shows an example of a white light emitting device according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and how to accomplish them, will become apparent with reference to the embodiments and drawings described in detail below. However, it is to be understood that the present invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. It is intended that the disclosure of the present invention be limited only by the terms of the appended claims.

Hereinafter, a method of manufacturing a color conversion material using the nano glass powder according to the present invention and a white light emitting device will be described in detail with reference to the accompanying drawings.

The method of manufacturing phosphor-based glass (PIG) according to the present invention uses nano glass powder having an average particle diameter of 100 nm or less.

In the case of a glass-based color conversion material, the glass firing temperature must be sufficiently high to suppress the occurrence of bubbles and obtain high light transmittance. However, in the case of such a high baking temperature, deterioration of the color conversion efficiency often occurs due to phosphor deterioration.

As disclosed in Korean Patent Laid-Open Publication No. 10-2009-0032639, in the case of glass powder, the smaller the size, the higher the melting degree and the firing temperature can be lowered. The present invention provides a method of manufacturing a color conversion material having excellent light transmittance and excellent color conversion efficiency by applying such characteristics.

The color conversion material manufacturing method according to the embodiment of the present invention may use a bulk firing method or a paste firing method.

In the case of the bulk calcination method, a nano glass powder having an average particle diameter of 100 nm or less is formed and mixed with a phosphor to form a mixture, followed by molding, followed by baking the formed body.

The phosphor may be included in an amount of about 3 to 70% by weight based on the total weight of the nano glass powder and the phosphor. The content of the phosphor can be controlled by the thickness of the color conversion material, the LED size, the number of LEDs, and the like.

In the case of the paste firing method, it may include a step of forming a nano glass powder having an average particle diameter of 100 nm or less, preparing a paste including a nano glass powder and a phosphor, applying the paste to the substrate glass, and then firing.

The paste may contain an organic solvent, an organic binder, etc., and these components are removed in the drying process and the firing process after the application of the paste.

On the other hand, the nano glass powder is composed of 55 to 70% of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% of CaO or less and 2 to 10% of SrO, ₂ O was added to (R = Li, Na, K , Rb and _{Cs), Sb 2 O 3,} F, Cl, this is by _{SO 3, P 2 O 5,} V 2 O 5, PbO, ZnO and Bi ₂ O ₃ It may not be. (Glass composition 1)

The nano glass powder contains 55 to 70% of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% or less of CaO, 2 to 10% of SrO, 5% or less, and BaO: is composed of at least one of 5 weight% or less _{kinds, R 2 O (R = Li} , Na, K, Rb and _{Cs), Sb 2 O 3,} F, Cl, SO 3, P 2 O 5, V ₂ O ₅ , PbO, ZnO and Bi ₂ O ₃ may not be intentionally added. (Glass composition 2)

The phosphor can be deteriorated not only at a high temperature but also by the glass itself.

In the case of the glass, the components which can be seen the reaction of the phosphor, for example, R ₂ O (R = Li, Na, K, Rb and Cs), Sb ₂ O _3, F, Cl, SO _3, P ₂ O ₅ , V ₂ O ₅ , PbO, ZnO, and Bi ₂ O ₃ can be prevented from being used to maximize the color conversion efficiency, and bubbling can be suppressed by baking at a temperature above the softening temperature for a short time So that the light transmittance and the light extraction efficiency can be improved.

Hereinafter, the role and content of each component will be described.

SiO ₂ contributes to the formation of a three-dimensional network structure to improve glass stability. The SiO ₂ is preferably added in an amount of 55 to 70% by weight based on the total weight of the glass. When the addition amount of SiO ₂ is less than 55% by weight, the effect of addition thereof is insufficient. On the other hand, when SiO ₂ exceeds 70% by weight, the glass softening temperature becomes excessively high.

Al ₂ O ₃ contributes to glass stabilization. The Al ₂ O ₃ is preferably added in an amount of 10 to 22% by weight based on the total weight of the glass. If the addition amount of Al ₂ O ₃ is less than 10% by weight, the effect of the addition is insufficient. On the contrary, when the amount of Al ₂ O ₃ added exceeds 22% by weight, the glass fluidity may be greatly reduced.

B ₂ O ₃ contributes to network formation and contributes to lowering the firing temperature through viscosity reduction. The B ₂ O ₃ is preferably added in an amount of 1 to 15% by weight based on the total weight of the glass. If the addition amount of B ₂ O ₃ is less than 1% by weight, the effect of the addition is insufficient. On the other hand, when the addition amount of B ₂ O ₃ exceeds 15% by weight, crystallization of glass can proceed rapidly.

CaO and SrO lower the softening temperature of the glass and contribute to lowering the firing temperature for the production of the color conversion glass. These components are preferably added in an amount of not more than 10% by weight of CaO and 2 to 10% by weight of SrO, and may further include not less than 5% by weight of MgO and not less than 5% by weight of BaO. Further, it is more preferable that the total sum of CaO, SrO, MgO and BaO is 10 to 25% by weight of the total weight of the glass. The softening temperature can be lowered in the above range without decreasing the light transmittance. If any component exceeds the above range, problems such as lowered fluidity and promotion of crystallization may occur.

The glass having the above composition may be produced by firing at a temperature of about 800 ° C or higher, which corresponds to a softening temperature or higher, when the microsize is about 100 μm, and when fining to a nano size, the firing temperature may be lowered to about 750 ° C or lower have. When firing at a temperature lower than the softening temperature of the glass powder, a large amount of bubbles are generated in the fired glass, thereby lowering light transmittance and light extraction efficiency. However, if the firing temperature exceeds 980 ° C and is too high, discoloration of the phosphor may occur.

The following experiment was conducted to evaluate the effect of the glass composition.

The phosphors were mixed in the same amounts as the glass powders having the glass compositions shown in Tables 1 and 2 below, molded into a plate shape, and then fired at the firing temperature shown in Table 3 for 30 minutes to prepare color conversion materials.

In Table 1 and Table 2, the units are parts by weight, and when the total amount is 100 parts by weight, they are the same as the weight%.

[Table 1]

[Table 2]

[Table 3]

(2) Basic color conversion glasses to which glass compositions 1 to 42 were applied were visually evaluated for the response of the phosphors, and evaluated according to the following criteria.

O: Excellent (no discoloration of the phosphor)

?: Normal (finely discolored phosphor)

X: Not applicable (discoloration of the phosphor)

Referring to Table 3, in the case of Specimens 38 to 41 satisfying the glass component proposed in the present invention, although the firing was performed at 800 ° C or more, the phosphor discoloration did not occur as a whole. However, in the case of the specimen 42, the firing was performed at an excessively high temperature of 1000 ° C, resulting in a slight discoloration of the phosphor.

However, in the case of the specimens 1 to 37, which did not satisfy the glass component proposed in the present invention, the phosphor discoloration occurred as a whole.

In the above-mentioned examples, glass powder having an average particle size of 100 mu m is used. When the glass powder is made fine with nano powder, the firing temperature can be lowered, and thus the effect of preventing deterioration of the phosphor can be further improved.

Further, the phosphor may be a (Lu _x Ce _{1 -x} ) ₃ Al ₅ O ₁₂ (0.75 _{? X} ? 0.95) phosphor. Generally, a YAG fluorescent material, (Sr _1.7 Ba _0.2 Eu _0.1 ) SiO ₄ fluorescent material, and a nitride fluorescent material are used as the blue excitation yellow light emitting fluorescent material. However, these phosphors are characterized in that when the temperature of the light emitting device rises to 200 ° C or higher due to the LED driving, the characteristics of the phosphor rapidly deteriorates.

(Lu _x Ce _1-x ) ₃ Al ₅ O ₁₂ (0.75 _{? X} ? 0.95) phosphors are mainly used as blue excitation green light emitting phosphors. However, when a (Lu _x Ce _{1 -x} ) ₃ Al ₅ O ₁₂ phosphor was fired like glass to produce a color conversion material, a white light was emitted. This is a result of the conversion of the color characteristic from the green to the yellow emission wavelength of the phosphor when the (Lu _x Ce _{1 -x} ) ₃ Al ₅ O ₁₂ phosphor is fired together with the glass.

Further, in the case of the (Lu _x Ce _1-x ) ₃ Al ₅ O ₁₂ phosphor, as shown in Fig. 1, which shows the characteristic change of the (Lu _0.9 Ce _0.1 ) ₃ Al ₅ O ₁₂ phosphor fired together with the glass , And the light output characteristic is not significantly lowered at a high temperature of 200 ° C or more. When the glass and the phosphor are sintered together, they can be regarded as a substitute for the conventional yellow phosphor.

2 schematically shows an example of a white light emitting device according to the present invention.

Referring to FIG. 2, a white light emitting device according to the present invention includes an LED 102 and a color conversion material 103. The LED 102 is mounted on the package body 101 and outputs blue light.

The color conversion material 103 is disposed on the front surface of the LED, and the color conversion material is formed by dispersing a yellow phosphor in glass, wherein the yellow phosphor has a composition of (Lu _x Ce _1-x ) ₃ Al ₅ O ₁₂ Lt; = 0.95).

At this time, the glass in _{weight%, SiO 2 55 ~ 70%} , Al 2 O 3 10 ~ 22%, B 2 O 3 1 ~ 15%, formed of a less CaO 10%, and _{SrO 2 ~ 10%, R 2} O (R = Li, Na, K , Rb and _{Cs), Sb 2 O 3,} F, Cl, SO 3, P 2 O 5, V 2 O 5, PbO, ZnO and Bi ₂ O ₃ is not intentionally added Lt; / RTI >

The glass contains, by weight, 55 to 70% of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% or less of CaO, 2 to 10% of SrO, 5% BaO: is composed of at least one of not more than 5% by weight of _{species, R 2 O (R = Li} , Na, K, Rb and _{Cs), Sb 2 O 3,} F, Cl, SO 3, P 2 O 5, V 2 O ₅ , PbO, ZnO and Bi ₂ O ₃ may not be intentionally added.

As described above, according to the method of producing a color conversion material using the nano glass powder according to the present invention, the firing temperature can be lowered without lowering the light transmittance by using the characteristic that the firing temperature is lowered as the size of the glass powder becomes nano , Thereby suppressing the phosphor reaction, thereby preventing deterioration in color conversion efficiency.

(Lu _x Ce _1-x ) ₃ Al ₅ O ₁₂ (0.75 _{? X} ? 0.95), which is mainly used as a green phosphor, was fired together with glass powder to prepare a color conversion material and applied to a white light emitting device. As a result, And at the same time, the effect of not lowering the light output characteristic even at a high temperature of 200 DEG C or more can be exerted.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is to be understood that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

101: Package body 102: LED chip
103: Color conversion glass

Claims (8)

1. A method of manufacturing a phosphor-in-glass (PIG)
Forming a nano glass powder having an average particle diameter of 100 nm or less;
Mixing the nano glass powder and the phosphor to form a mixture;
Forming a molded body by molding the mixture; And
And firing the formed body. ≪ Desc / Clms Page number 19 >
A method of manufacturing a color conversion material disposed on a front surface of an LED,
Forming a nano glass powder having an average particle diameter of 100 nm or less;
Preparing a paste including the nano glass powder and the phosphor; And
Applying the paste to a substrate glass, and firing the paste.
3. The method according to claim 1 or 2,
The nano glass powder
Wherein the composition comprises 55 to 70% of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% of CaO or less and 2 to 10% of SrO,
R ₂ O (R = Li, Na, K, Rb and Cs), Sb ₂ O ₃ , F, Cl, SO ₃ , P ₂ O ₅ , V ₂ O ₅ , PbO, ZnO and Bi ₂ O ₃ Wherein the color conversion material is not added.
3. The method according to claim 1 or 2,
The nano glass powder
Wherein the composition comprises 55 to 70% by weight of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% or less of CaO, 2 to 10% of SrO, % Or less,
R ₂ O (R = Li, Na, K, Rb and Cs), Sb ₂ O ₃ , F, Cl, SO ₃ , P ₂ O ₅ , V ₂ O ₅ , PbO, ZnO and Bi ₂ O ₃ Wherein the color conversion material is not added.
3. The method according to claim 1 or 2,
Wherein the phosphor is a (Lu _x Ce _{1 -x} ) ₃ Al ₅ O ₁₂ (0.75 _{? X} ? 0.95) phosphor.
LED and a phosphor in glass (PIG) disposed on the front surface of the LED,
The LED emits blue light,
Wherein the color conversion material is a phosphor in which yellow phosphor is dispersed in glass, and the yellow phosphor is (Lu _x Ce _1-x ) ₃ Al ₅ O ₁₂ (0.75 _{? X} ? 0.95) phosphor.
The method according to claim 6,
The glass
Wherein the composition comprises 55 to 70% of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% of CaO or less and 2 to 10% of SrO,
R ₂ O (R = Li, Na, K, Rb and Cs), Sb ₂ O ₃ , F, Cl, SO ₃ , P ₂ O ₅ , V ₂ O ₅ , PbO, ZnO and Bi ₂ O ₃ Is not added.
The method according to claim 6,
The glass
Wherein the composition comprises 55 to 70% by weight of SiO ₂ , 10 to 22% of Al ₂ O ₃ , 1 to 15% of B ₂ O ₃ , 10% or less of CaO, 2 to 10% of SrO, % Or less,
R ₂ O (R = Li, Na, K, Rb and Cs), Sb ₂ O ₃ , F, Cl, SO ₃ , P ₂ O ₅ , V ₂ O ₅ , PbO, ZnO and Bi ₂ O ₃ Is not added.

Images